Microoptimization to regexps.

src/arm/code-stubs-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5214 matching lines @@
   // r0: JSArray, tagged.
   // r3: FixedArray, tagged.
   // r5: Number of elements in array, untagged.
 
   // Set map.
   __ mov(r2, Operand(factory->fixed_array_map()));
   __ str(r2, FieldMemOperand(r3, HeapObject::kMapOffset));
   // Set FixedArray length.
   __ mov(r6, Operand(r5, LSL, kSmiTagSize));
   __ str(r6, FieldMemOperand(r3, FixedArray::kLengthOffset));
-  // Fill contents of fixed-array with the-hole.
-  __ mov(r2, Operand(factory->the_hole_value()));
+  // Fill contents of fixed-array with undefined.
+  __ LoadRoot(r2, Heap::kUndefinedValueRootIndex);
   __ add(r3, r3, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-  // Fill fixed array elements with hole.
+  // Fill fixed array elements with undefined.
   // r0: JSArray, tagged.
-  // r2: the hole.
+  // r2: undefined.
   // r3: Start of elements in FixedArray.
   // r5: Number of elements to fill.
   Label loop;
   __ cmp(r5, Operand(0));
   __ bind(&loop);
   __ b(le, &done);  // Jump if r5 is negative or zero.
   __ sub(r5, r5, Operand(1), SetCC);
   __ str(r2, MemOperand(r3, r5, LSL, kPointerSizeLog2));
   __ jmp(&loop);
 
@@ skipping 2362 matching lines @@
 
   __ Pop(lr, r5, r1);
   __ Ret();
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM